sunny atmospheric

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Resources
 Science news story.
 Word bank.
 Activity 1: Mixed-up meanings.
 Activity 2: Comprehension.
 Activity 3: Find the missing word.
 Activity 4: What kind of statements?
 Activity 5: Topics for discussion, research or presentation.
News
Boulder, Colorado : Embargoed for release: 30-Aug-2007 14:00 Eastern
US Time
Sunny waves
The sun is the most familiar object in the sky - at least it was until this
summer. It is also one of the best understood. But there are still some
deep mysteries about what happens there.
real
science
One of the most puzzling is the fact that the outer layers of the sun’s
atmosphere, which is called the corona, is far hotter than the surface of
the sun. This is very hard to understand. Scientists have compared it to a
kettle boiling merrily on top of a block of ice.
One possible explanation is that heat is carried upwards by a special kind
of wave called an Alfvén wave. Now scientists for the first time have
observed Alfvén waves in the corona.
The discovery gives them an insight into the behavior of the sun and its
magnetic field. It should also lead to a better understanding of how the
sun affects the earth and the rest of the solar system.
The research was led by Steve Tomczyk of the National Center for
Atmospheric Research (NCAR). It is published this week in Science.
"Alfvén waves can provide us with a window into processes that are
fundamental to the workings of the sun," says Tomczyk.
Alfvén waves are fast-moving disturbances that carry energy. They move
out from the sun along magnetic field lines. They have been detected in
space well beyond the Sun. But they have never before been seen within
the corona.
Alfvén waves are hard to detect. This is partly because, unlike other types
of wave, they don’t create large disturbances in the corona. Also the
changes in velocity they cause are small and not easily noticed.
"Our observations allowed us to unambiguously identify these
oscillations as Alfvén waves," says co-author Scott McIntosh. He is at the
Southwest Research Institute in Boulder.
"The waves are visible all the time and they occur all over the corona.”
This was a surprise to the researchers, he added.
By tracking the speed and direction of the waves, researchers should now
be able to work out basic properties of the sun’s atmosphere. These
include its density and the direction of its magnetic fields.
The research may also help scientists to predict solar storms. These are
extremely violent events that spew thousands of tons of matter into space
in the form of energetic particles.
real
science
When these particles hit earth’s atmosphere they cause the aurora
borealis, the northern lights. They can also have much less appealing
effects, by blocking radio signals, causing electrical blackouts and
damaging satellites. In March 1989 a solar storm caused a complete
blackout of the city of Quebec.
Learning more about solar storms might also help to protect astronauts
from dangerous levels of radiation in space.
"If we want to go to the moon and Mars, people need to know what's
going to happen on the sun," Tomczyk says.
To observe the waves, Tomczyk and his colleagues used an instrument
developed at the National Center for Atmospheric Research over the last
few years.
The coronal multichannel polarimeter (CoMP) is attached to a telescope
at the National Solar Observatory in New Mexico. It is a special
instrument designed to gather light from the corona. This is much dimmer
than the sun itself so is difficult to see against its glare.
The CoMP then tracks magnetic activity around the entire edge of the
sun. It works fast, making a measurement as often as once every 15
seconds.
With the help of this instrument the research team were able to capture
intensity and velocity measurements and polarization images of the solar
corona, all at the same time.
Those measurements and images revealed waves that were moving in
paths that lined up with magnetic fields, and traveled at almost 2,500
miles per second.
So can these newly-discovered waves explain why the corona is so very
hot? Well maybe. The Alfvén waves the researchers actually observed
were, they say, too weak to heat the corona.
But the possibility remains that other, stronger Alfvén waves carry
enough energy to do so.
The mystery of why the kettle is boiling on the block of ice has not yet
been completely solved.
real
science
###
In addition to Tomczyk and McIntosh, the research team included
scientists from the National Solar Observatory, University of Notre
Dame, Framingham High School in Massachusetts, University of
Michigan, and NCAR.
Title: "Alfvén Waves in the Solar Corona"
Authors: S. Tomczyk, S.W. McIntosh, S.L. Keil, P.G. Judge, T. Schad,
D.H. Seeley, J. Edmondson
Publication: Science, August 31, 2007
700 words
Flesch reading ease: 62.1
Flesch-Kincaid Grade level: 8.3
real
science
Word bank
Pupils will not know some of the words used in the text. Meanings are
given below, followed by an exercise in matching words and meanings.
Teachers may choose to provide some or all of the meanings to help
pupils read and understand the story. An approach that leads to better
learning is to ask pupils to complete as much of Activity 1 as possible
during their first encounter with the text.
By tackling this exercise and those that follow – which are known
collectively as directed activities related to texts (DARTs) – pupils can
engage with a piece of writing, and learn a great deal from it, even when
many of its ideas and words are unfamiliar to them.
Word
1
2
activity
aurora borealis
3
4
5
6
basic
behavior
blackout
co-author
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
colleagues
compared
corona
designed
detect
detected
energetic
energy
explanation
familiar
fundamental
identify
insight
intensity
magnetic field
Meaning
lively action
brilliant lights in the sky caused by the solar
wind
forming the first or most important parts
how something acts
total loss of electricity in a town or city
person who has written something along
with someone else
people who work together
studied to see what is the same or different
thin outer layer of the sun's atmosphere
thought up and made especially to
discover
discovered
having great energy
ability to do work
something that explains
well-known; often seen
basic and essential
recognize as something
seeing how a thing works
rate of flow of energy
region around a magnet where its
magnetism can affect other objects
real
science
22
23
24
25
26
mysteries
observed
oscillations
particles
polarization
27 processes
28 radiation
29 research
30 researchers
31 satellites
32 solar
33 solar system
34
35
36
37
38
temperature
unambiguously
velocity
visible
wave
39 window
40 atmosphere
41 disturbances
42 orbit
43 orbits
44 plane
45 planet
46 vibration
things that can’t be explained or understood
seen and noticed, especially in science
steady back and forth swinging; waves
very small pieces of matter
the plane in which a wave motion takes
place
series of actions that make or do something
particles or waves that carry energy and are
given out by something
careful study to find out facts or information
people who study something carefully to
find out facts or information
human-built objects that orbit the earth
of the sun
the sun and all the planets, moons, asteroids,
comets, lumps of rock and dust in orbit
around it
a measure of hotness or coldness
very clearly
speed in a particular direction
able to be seen
a disturbance or vibration that carries energy
from one place to another
way to see
the mixture of gases around a planet, star or
our sun
movements from a normal position
path followed by one body around another
moves in a curved path around a sun, planet
or other object in space
flat surface
large body of rock or gas in orbit around a
star or our sun
repeated back and forth motion
real
science
Activity 1
Mixed-up meanings
Pupils should try to fill in the blanks in the final column with the words
that match the meanings. The words needed are listed, but not necessarily
in the right order, in the first column.
This exercise should not be tackled in isolation, but by a reader with
access to the story itself: The contexts in which words are used provide
powerful clues to their meanings.
1
2
Word
activity
aurora borealis
3
basic
4
5
behavior
blackout
6
7
8
9
co-author
colleagues
compared
corona
10
designed
11
12
detect
detected
13
energetic
14
15
energy
explanation
16
17
familiar
fundamental
18
identify
Meaning
lively action
forming the first or most
important parts
person who has written
something along with
someone else
seeing how a thing works
things that can’t be explained
or understood
something that explains
well-known; often seen
very clearly
thin outer layer of the sun's
atmosphere
particles or waves that carry
energy and are given out by
something
ability to do work
path followed by one body
around another
thought up and made
especially to
of the sun
the sun and all the planets,
moons, asteroids, comets,
lumps of rock and dust in orbit
around it
very small pieces of matter
large body of rock or gas in
orbit around a star or our sun
having great energy
real
science
Word should be
19
insight
20
21
intensity
magnetic field
22
mysteries
23
24
25
observed
oscillations
particles
26
polarization
27
28
processes
radiation
29
research
30
31
32
researchers
satellites
solar
33
solar system
34
35
36
temperature
unambiguously
velocity
37
visible
38
39
wave
window
40
atmosphere
41
disturbances
42
orbit
a disturbance or vibration that
carries energy from one place
to another
people who work together
people who study something
carefully to find out facts or
information
human-built objects that orbit
the earth
discover
recognize as something
a measure of hotness or
coldness
careful study to find out facts
or information
discovered
movements from a normal
position
moves in a curved path around
a sun, planet or other object in
space
rate of flow of energy
able to be seen
brilliant lights in the sky
caused by the solar wind
steady back and forth
swinging; waves
how something acts
basic and essential
region around a magnet where
its magnetism can affect other
objects
repeated back and forth
motion
way to see
total loss of electricity in a
town or city
the plane in which a wave
motion takes place
the mixture of gases around a
planet, star or our sun
flat surface
real
science
43
orbits
44
plane
45
46
planet
vibration
studied to see what is the same
or different
seen and noticed, especially in
science
speed in a particular direction
series of actions that make or
do something
real
science
Activity 2
What’s it all about?
1. What is the most familiar object in the sky?
2. Do we know everything there is to know about this object?
3. What word near the start of the story gave you the answer to that last
question?
4. The heat of the sun is created deep beneath its surface, so this
surface is not nearly as hot as its centre. That also means that it
should be cooler far out from the surface. Is it?
5. What have scientists compared this to?
6. One explanation of this mystery is that Alfvén waves carry heat
outwards. Have these Alfvén waves been observed before in the
corona?
7. The story mentions two areas where our understanding will improve
through the Alfvén wave discovery. State one of them.
8. Give one reason for Alfvén waves being hard to detect.
9. Are the scientists certain that what their instruments detected are
Alfvén waves?
10.What word in the story gave you the answer to the last question?
11.By tracking the Alfvén waves, scientists will now be able to learn
more about the sun’s magnetic ------.
12.The work might also help scientists to predict what?
13.Give two reasons that would be very useful.
14.Why did the scientists have to use a special instrument to study the
corona, instead of just looking at photographs taken through a normal
telescope?
15.Apart from enabling the scientists to take images of the corona what
else can the CoMP do?
real
science
16.The writer mentions three pieces of information that the CoMP was
able to obtain at lots of different places in the corona. State two of
these.
17.Putting all this information together allowed the scientists see that
waves were travelling through the corona at almost 2,500 miles per
second. In what direction?
18.Explain in one sentence why this is not the whole answer to the puzzle
of the corona’s high temperature.
19.If you were these scientists what would you like to study next?
20.What question would that research be trying to answer?
real
science
Activity 3
Find the missing word
Pupils should try to fill in the blanks using clues from the rest of the
sentence. When in doubt, the length of each blank indicates the length of
the missing word. A complete list of words that belong in the blanks is
provided at the end of the passage.
Sunny waves
The sun is the most familiar object in ___ sky - at least it was until this
summer. __ is also one of the best understood. But there ___ still some
deep mysteries about what happens there.
One of ___ most puzzling is the fact that the temperature in the _____
layers of the sun’s atmosphere, which is called the corona, is far ______
than it is at the surface of the sun. This is very ____ to understand.
Scientists have compared it to a kettle _______ merrily on top of a block
of ice.
One ________ explanation is that heat is carried upwards by a _______
kind of wave called an Alfvén wave. Now scientists ___ the first time
have observed Alfvén waves in the ______.
The discovery gives them an insight ____ the behavior of the sun and its
magnetic field. __ should also lead to a better understanding of how ___
sun affects the earth and the rest of the _____ system.
The research was led by Steve Tomczyk of the ________ Center for
Atmospheric Research (NCAR). It is published this ____ in Science.
"Alfvén waves can provide us with a window ____ processes that are
fundamental to the workings of the ___," says Tomczyk.
Alfvén waves are fast-moving disturbances that carry ______. They move
out from the sun along magnetic _____ lines. They have been detected in
space well beyond ___ Sun. But they have never before been seen within
___ corona.
real
science
Alfvén waves are hard to detect. This is ______ because, unlike other
types of wave, they don't create _____ disturbances in the corona. Also
the changes in velocity ____ cause are small and not easily noticed.
"Our observations allowed __ to unambiguously identify these
oscillations as Alfvén waves," says _________ Scott McIntosh. He is at
the Southwest Research Institute __ Boulder.
"The waves are visible all the time and ____ occur all over the corona."
This was a surprise __ the researchers, he added.
By tracking the speed and _________ of the waves, researchers should
now be able to ____ out basic properties of the sun's atmosphere. These
include ___ density and the direction of its magnetic fields.
The ________ may also help scientists to predict solar storms. These ___
extremely violent events that spew thousands of tons of ______ into
space in the form of energetic particles.
When _____ particles hit earth's atmosphere they cause the aurora
borealis, ___ northern lights. They can also have much less appealing
_______, by blocking radio signals, causing electrical blackouts and
________ satellites. In March 1989 a solar storm caused a ________
blackout of the city of Quebec.
Learning more about _____ storms might also help to protect astronauts
from dangerous ______ of radiation in space.
"If we want to go to ___ moon and Mars, people need to know what's
going __ happen on the sun," Tomczyk says.
To observe the waves, _______ and his colleagues used an instrument
developed at the ________ Center for Atmospheric Research over the last
few years.
The coronal multichannel polarimeter (CoMP) is attached to a _________
at the National Solar Observatory in New Mexico. It __ a special
instrument designed to gather light from the ______. This is much
dimmer than the sun itself __ is difficult to see against its glare.
The CoMP ____ tracks magnetic activity around the entire edge of the
___. It works fast, making a measurement as often __ once every 15
seconds.
real
science
With the help of this instrument ___ research team were able to capture
intensity and velocity ____________ and polarization images of the solar
corona, all at ___ same time.
Those measurements and images revealed waves that were moving __
paths that lined up with magnetic fields, and traveled __ almost 2,500
miles per second.
So can these newly-discovered waves _______ why the corona is so very
hot? Well maybe. ___ Alfvén waves the researchers actually observed
were, they say, ___ weak to heat the corona.
But the possibility remains ____ other, stronger Alfvén waves carry
enough energy to do __.
The mystery of why the kettle is boiling on ___ block of ice has not yet
been completely solved.
These are all the words that belong in the blanks:
are, are, as, at, atmosphere, boiling, co-author, complete, corona, corona,
damaging, direction, effects, energy, explain, field, for, hard, higher, in,
in, into, into, is, It, It, its, large, levels, matter, measurements, National,
National, outer, partly, possible, research, so, so, solar, solar, special, sun,
sun, telescope, that, the, the, the, the, the, the, the, the, the, The, the, then,
these, they, they, to, to, Tomczyk, too, us, week, work
real
science
Answer Key:
Sunny waves
The sun is the most familiar object in the sky - at least it was until this
summer. It is also one of the best understood. But there are still some
deep mysteries about what happens there.
One of the most puzzling is the fact that the temperature in the outer
layers of the sun’s atmosphere, which is called the corona, is far higher
than it is at the surface of the sun. This is very hard to understand.
Scientists have compared it to a kettle boiling merrily on top of a block of
ice.
One possible explanation is that heat is carried upwards by a special kind
of wave called an Alfvén wave. Now scientists for the first time have
observed Alfvén waves in the corona.
The discovery gives them an insight into the behavior of the sun and its
magnetic field. It should also lead to a better understanding of how the
sun affects the earth and the rest of the solar system.
The research was led by Steve Tomczyk of the National Center for
Atmospheric Research (NCAR). It is published this week in Science.
"Alfvén waves can provide us with a window into processes that are
fundamental to the workings of the sun," says Tomczyk.
Alfvén waves are fast-moving disturbances that carry energy. They move
out from the sun along magnetic field lines. They have been detected in
space well beyond the Sun. But they have never before been seen within
the corona.
Alfvén waves are hard to detect. This is partly because, unlike other
types of wave, they don't create large disturbances in the corona. Also the
changes in velocity they cause are small and not easily noticed.
"Our observations allowed us to unambiguously identify these
oscillations as Alfvén waves," says co-author Scott McIntosh. He is at
the Southwest Research Institute in Boulder.
real
science
"The waves are visible all the time and they occur all over the corona."
This was a surprise to the researchers, he added.
By tracking the speed and direction of the waves, researchers should now
be able to work out basic properties of the sun's atmosphere. These
include its density and the direction of its magnetic fields.
The research may also help scientists to predict solar storms. These are
extremely violent events that spew thousands of tons of matter into space
in the form of energetic particles.
When these particles hit earth's atmosphere they cause the aurora
borealis, the northern lights. They can also have much less appealing
effects, by blocking radio signals, causing electrical blackouts and
damaging satellites. In March 1989 a solar storm caused a complete
blackout of the city of Quebec.
Learning more about solar storms might also help to protect astronauts
from dangerous levels of radiation in space.
"If we want to go to the moon and Mars, people need to know what's
going to happen on the sun," Tomczyk says.
To observe the waves, Tomczyk and his colleagues used an instrument
developed at the National Center for Atmospheric Research over the last
few years.
The coronal multichannel polarimeter (CoMP) is attached to a telescope
at the National Solar Observatory in New Mexico. It is a special
instrument designed to gather light from the corona. This is much
dimmer than the sun itself so is difficult to see against its glare.
The CoMP then tracks magnetic activity around the entire edge of the
sun. It works fast, making a measurement as often as once every 15
seconds.
With the help of this instrument the research team were able to capture
intensity and velocity measurements and polarization images of the solar
corona, all at the same time.
Those measurements and images revealed waves that were moving in
paths that lined up with magnetic fields, and traveled at almost 2,500
miles per second.
real
science
So can these newly-discovered waves explain why the corona is so very
hot? Well maybe. The Alfvén waves the researchers actually observed
were, they say, too weak to heat the corona.
But the possibility remains that other, stronger Alfvén waves carry
enough energy to do so.
The mystery of why the kettle is boiling on the block of ice has not yet
been completely solved.
real
science
Activity 4
What kind of statement?
Students should read the news story on page 1 about the latest scientific
research, and highlight phrases or sentences according to the following
key (or any other way of indicating the different types of statement that
can be done with the resources in their pockets or in your classroom):
Existing knowledge
Aims/reasons for doing the research
Technology and methods
New findings or developments
Hypothesis
Prediction
Evidence
IIssssuueess,, iim
mpplliiccaattiioonnss aanndd aapppplliiccaattiioonnss
Normally no more than one phrase or sentence should be highlighted in
each paragraph, unless the reader decides that a particular paragraph
contains several really important ideas.
Usually the decision will not be too difficult. But choosing between, say,
hypotheses and new findings can sometimes be tricky. There isn’t always
an obviously right or wrong answer, even to the scientists themselves.
Pupils should be encouraged not to agonize too long over their choice of
statement type, but to be prepared to give reasons for their decisions.
Note: A hypothesis is a “tentative explanation that leads to predictions
that can be tested by experiment or observation”.
Answer Key: (These are illustrative choices. There are many others.)
Sunny waves
The sun is the most familiar object in the sky - at least it was until this
summer. It is also one of the best understood. But there are still some
deep mysteries about what happens there.
One of the most puzzling is the fact that the temperature in the outer
layers of the sun’s atmosphere, which is called the corona, is far higher
real
science
than it is at the surface of the sun. This is very hard to understand.
Scientists have compared it to a kettle boiling merrily on top of a block of
ice.
One possible explanation is that heat is carried upwards by a special kind
of wave called an Alfvén wave. Now scientists for the first time have
observed Alfvén waves in the corona.
The discovery gives them an insight into the behavior of the sun and its
magnetic field. It should also lleeaadd ttoo aa bbeetttteerr uunnddeerrssttaannddiinngg ooff hhoow
w tthhee
ssuunn aaffffeeccttss tthhee eeaarrtthh aanndd tthhee rreesstt ooff tthhee ssoollaarr ssyysstteem
m..
The research was led by Steve Tomczyk of the National Center for
Atmospheric Research (NCAR). It is published this week in Science.
"A
Allffvvéénn w
waavveess ccaann pprroovviiddee uuss w
wiitthh aa w
wiinnddoow
w iinnttoo pprroocceesssseess tthhaatt aarree
ffuunnddaam
meennttaall ttoo tthhee w
woorrkkiinnggss ooff tthhee ssuunn," says Tomczyk.
Alfvén waves are fast-moving disturbances that carry energy. They move
out from the sun along magnetic field lines. They have been detected in
space well beyond the Sun. But they have never before been seen within
the corona.
Alfvén waves are hard to detect. This is partly because, unlike other types
of wave, they don’t create large disturbances in the corona. Also the
changes in velocity they cause are small and not easily noticed.
"Our observations allowed us to unambiguously identify these
oscillations as Alfvén waves," says co-author Scott McIntosh. He is at the
Southwest Research Institute in Boulder.
"The waves are visible all the time and they occur all over the corona.”
This was a surprise to the researchers, he added.
By tracking the speed and direction of the waves, rreesseeaarrcchheerrss sshhoouulldd
nnoow
w bbee aabbllee ttoo w
woorrkk oouutt bbaassiicc pprrooppeerrttiieess ooff tthhee ssuunn’’ss aattm
moosspphheerree.
These include its density and the direction of its magnetic fields.
T
Thhee rreesseeaarrcchh m
maayy aallssoo hheellpp sscciieennttiissttss ttoo pprreeddiicctt ssoollaarr ssttoorrm
mss.. These
are extremely violent events that spew thousands of tons of matter into
space in the form of energetic particles.
real
science
When these particles hit earth’s atmosphere they cause the aurora
borealis, the northern lights. They can also have much less appealing
effects, by blocking radio signals, causing electrical blackouts and
damaging satellites. In March 1989 a solar storm caused a complete
blackout of the city of Quebec.
Learning more about solar storms might also hheellpp ttoo pprrootteecctt aassttrroonnaauuttss
ffrroom
m ddaannggeerroouuss lleevveellss ooff rraaddiiaattiioonn iinn ssppaaccee..
"IIff w
wee w
waanntt ttoo ggoo ttoo tthhee m
moooonn aanndd M
Maarrss,, ppeeooppllee nneeeedd ttoo kknnoow
ww
whhaatt''ss
ggooiinngg ttoo hhaappppeenn oonn tthhee ssuunn,,"" Tomczyk says.
To observe the waves, Tomczyk and his colleagues used an instrument
developed at the National Center for Atmospheric Research over the last
few years.
The coronal multichannel polarimeter (CoMP) is attached to a telescope
at the National Solar Observatory in New Mexico. It is a special
instrument designed to gather light from the corona. This is much dimmer
than the sun itself so is difficult to see against its glare.
The CoMP then tracks magnetic activity around the entire edge of the
sun. It works fast, making a measurement as often as once every 15
seconds.
With the help of this instrument the research team were able to capture
intensity and velocity measurements and polarization images of the solar
corona, all at the same time.
Those measurements and images revealed waves that were moving in
paths that lined up with magnetic fields, and traveled at almost 2,500
miles per second.
SSoo ccaann tthheessee nneew
wllyy--ddiissccoovveerreedd w
waavveess eexxppllaaiinn w
whhyy tthhee ccoorroonnaa iiss ssoo
vveerryy hhoott?? Well maybe. The Alfvén waves the researchers actually
observed were, they say, too weak to heat the corona.
But the possibility remains that other, stronger Alfvén waves carry
enough energy to do so.
The mystery of why the kettle is boiling on the block of ice has not yet
been completely solved.
real
science
Activity 5 Topic for discussion, research or pupil
presentations
Stanford University has an excellent collection of sun science
investigations, activities and discussion topics at http://solarcenter.stanford.edu/teachers/lessons.html
These include retrieving solar images, understanding the solar scale
and an interview with Mr Sol (http://solarcenter.stanford.edu/interview/questions.html):
"Have you ever wondered what our star thinks about his (or her?) role
up there in the sky? Have you considered what an awesome
responsibility it must be, generating all that heat and light from fusion
and having so many living beings depending upon you?
Sol really does light up our life. Imagine what he might say if you
could interview him. Why don't you do a little research (this web site is
a good place to start) and then you and a friend create your own
interview with Mr. Sol!
If you come up with a good interview, send it to us and we'll publish it
here on the web!"
Tips for science class discussions and groupwork
No 60
Your students may not have the reasoning skills, or may not have the requisite prior
knowledge to solve the problem you have given them. In either case you need to
develop interventions which will chunk the ideas smaller while still giving them space
to learn for themselves.
Our inclination in this case, based on our own learning experiences as students, is to
tell the students things they need to know to solve the problem. In so doing you take
away, as you have pointed out, opportunities for them to learn. Perhaps you are telling
too much and not instead developing a set of questions for the students to work on and
discuss that will lead them to where you when you want them to be.
....
Sometimes it seems to me that my students have a little mental switch
in their heads, and I have to ask the right question to get them to
turn it on.
real
science
Often the question is "Explain your reasoning."
Extract from a contribution to an NSTA teachers' forum by Joseph J.
Bellina, Professor of Physics at Saint Mary's College, Notre Dame,
Indiana
real
science
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